Abstract : An optical computing device was designed using the Fourier transform properties of simple convex lenses and laser illumination. Input data was transferred from magnetic tape to photographic film via cathode ray tube and a camera of original design. The film transparency was then placed in the optical section and the power spectrum of the input data was recorded on film in the output plane. A microdensitometer was used to graph the power spectrum. A comparison of the experimental values with theoretical predictions was made and the results show that when discrepancies appear they are small and their source predictable. (Author)